<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
</head>
<body>
    <div id="box">
        {{name + '-aaa'}}
        {{10+20}}
        {{isLogin?"已登录":"未登录"}}
        {{name.slice(0,1)}}
        <div v-html="myhtml"></div>
    </div>
    <script>
        var obj = {
            data() {
                return {
                    name:"aaa",
                    isLogin:'true',
                    myhtml:'<p>aaaa<p>'
                }
            },
        }
        Vue.createApp(obj).mount('#box')
    </script>
</body>
</html>